1. Field
Aspects of embodiments according to the present invention relate in general to signal processing and more particularly to signal processing of multiple sensor data to enhance detection and geolocation of targets.
2. Description of Related Art
The detection and geolocation accuracy of targets (stationary or moving) by using multistatic data, such as the radar signal data received by multiple sensors (for example, airborne sensors), can present many problems. One possibility to address one or more of these problems is to use post-detection fusion of the multiple receivers' data. However, if one or more of the receivers has a low signal-to-noise ratio (SNR) while the others may have high SNR, the target geolocation accuracy may be seriously degraded. Another possibility is to use individual sensor range and Doppler measurements to detect and geolocate targets. However, this technique may not result in combined processing gain that can be obtained from multiple receivers, and it may be more difficult to detect or geolocate targets in clutter, especially slow moving targets. Yet another possibility is to use noncoherent combined processing. This, however, fails to make use of coherent data from multiple sensors. A still other possibility is to use post-detection measurements (bistatic range, bistatic Doppler) to geolocate the target. This approach, however, assumes that detection has already been performed and yielded “good” measurements, which is not generally true under low SNR conditions.
The need to improve air and ground moving target indication in difficult environments may necessitate the use of multiple spatially-separated receiving sensors deployed with one or more transmitters, which can also be referred to as a multistatic radar system. The use of a multistatic radar system can provide a significant improvement in target detection and geolocation performance, especially for slow moving targets embedded in clutter.